Author

Degree

Master of Science

Program

Geology

Supervisor

Dr. A. Guy Plint

Abstract

The Lower Colorado allogroup of the Western Canada Foreland Basin is a mud-dominated rock succession of marine, estuarine, and coastal plain depositional origin. Relative sea-level oscillations produced bounding discontinuities that allow the allogroup to be divided into four alloformations: the Joli Fou, Viking, Westgate, and Fish Scales.

Rocks of the Lower Colorado allogroup within the study area record marine depositional environments represented by 9 facies. The facies represent depositional environments ranging from offshore marine to lower shoreface through to upper shoreface and river mouth environments.

Geometric analysis of the isopach maps of the regional allomembers of the Lower Colorado allogroup has allowed the recognition and differentiation of the tectonic and eustatic contributions to the generation of accommodation patterns within the study area. Accommodation for the Joli Fou alloformation and allomembers VA and VB of the Viking alloformation were determined to be the result of eustatic changes, while allomembers VD, WB, WC, and FB were determined to be the result of tectonism.

Analysis of Viking allomembers VA, VB1, and VB2 revealed multiple internal surfaces that lead to the identification and mapping of sand bodies within the Viking allomembers. This identification led to the creation of a hypothetical sea-level curve that illustrates how sea-level changed during the Viking from the transgression of VE0 to the transgression of VE3.